Ruby on rails 确定ActiveRecord对象是否为新对象
如何检查Ruby on rails 确定ActiveRecord对象是否为新对象,ruby-on-rails,activerecord,Ruby On Rails,Activerecord,如何检查ActiveRecord对象是新对象还是已被持久化?只执行以下操作: object.new_record? ActiveRecord对象生命周期: 1.新记录 item = Item.new item.new_record? #=> true item.save item.persisted? #=> true item.name = "other" item.changed? #=> true item.destroy item.destroyed? #=&g
ActiveRecord
对象是新对象还是已被持久化?只执行以下操作:
object.new_record?
ActiveRecord对象生命周期: 1.新记录
item = Item.new
item.new_record? #=> true
item.save
item.persisted? #=> true
item.name = "other"
item.changed? #=> true
item.destroy
item.destroyed? #=> true
2.持续存在
item = Item.new
item.new_record? #=> true
item.save
item.persisted? #=> true
item.name = "other"
item.changed? #=> true
item.destroy
item.destroyed? #=> true
3.已更改
item = Item.new
item.new_record? #=> true
item.save
item.persisted? #=> true
item.name = "other"
item.changed? #=> true
item.destroy
item.destroyed? #=> true
4.销毁
item = Item.new
item.new_record? #=> true
item.save
item.persisted? #=> true
item.name = "other"
item.changed? #=> true
item.destroy
item.destroyed? #=> true